Question 895735
A company that makes cola drinks states that the mean caffeine content per one 12-ounce bottle of cola is 55 milligrams. 
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You work as a quality control manager and are asked to test this claim. 
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During your tests, you find that a random sample of 30 12-ounce bottles of cola has a mean caffeine content of 56.4 milligrams with standard deviation of 7.7 milligrams. 
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At α = 0.09, can you reject the company’s claim? Complete parts (a) - (e).
 a)Identify Ho, and Ha
Ho: u = 55 (claim)
Ha: u # 55
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b) Find the critical value(s). Selct the correct choice below and fill in the answer box within your choice
 (Round to two decimal places as needed)
 A) The critical values are +/- 1.6954___
 
Identify the rejection regions choose the correct answer 
(These are graphs)
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Test statistic::
z(56.4) =(56.4-55)/[7.7/sqrt(30)] = 0.9959
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 1 Reject Ho, Fail to reject Ho, Reject Ho
 2) Fail to reject Ho, Reject Ho
 3) Reject Ho, Fail to reject Ho 
c) Find the standardized test statistic
 Z= 0.9959___ 
d) Decide whether to reject or fail to reject the null hypothesis 
A) Since z is not in the rejection region, reject the null
 B) Since z is in the rejection region reject the null
 C) Since z is not in the rejection region fail to reject the null
 D) Since z is in the rejection region fail to reject the null 
And: C
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e) Interpret the decision in the context of the original claim 
At the 9% significance level there is not enough evidence to Reject the company's claim that the mean caffeine content per 12-ounce bottle of cola 
is equal to 56.4 milligrams.
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Cheers,
Stan H.
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